Integrated circuit (IC) performance can be limited by constraints posed by off-chip communication speed. Electrical interconnections offer only relatively low data rates. Optical communication can be faster, but unfortunately optical interconnections formed using optical devices embedded in silicon occupy valuable substrate real estate that cannot also be used for conventional integrated device circuits. What is needed is an optical interconnection approach for integrated circuits that offers high bandwidth and minimizes consumption of semiconductor area to the exclusion of other circuitry.
Moreover, conventional electro-optic modulation materials such as lithium niobate (LiNbO3) can suffer from requirements for high modulation voltage and can pose contamination problems if used in a silicon IC fabrication facility. What is needed is an optical material that can form active and passive optical devices without posing a substantial contamination risk to a semiconductor processing facility. What is also needed is an optical material that can be formed to include active devices having modulation voltages that are available on a conventional IC. What is also needed is an optical material that can be processed under conditions (e.g., temperature) that do not degrade underlying IC structures.